WASHINGTON - A new paper by the Center for Economic and Policy Research (CEPR) finds that half of all ballot boxes suffer from “adding up” errors, and the withholding of information by Mexico’s electoral authorities has undermined the credibility of election results.

“Mexico’s electoral authorities conducted a partial recount of 9 percent of the votes from August 9 to August 13,” said economist Mark Weisbrot, Co-Director of CEPR and co-author of the report. “There is no obvious legitimate reason for refusing to announce the results of this recount.”

Weisbrot noted that the recount was conducted very much like the preliminary and second vote counts, although independent observers were not allowed to witness the recount. Ballot boxes were opened, ballots counted, totals recorded, and tally sheets signed by witnesses and judges. In the previous vote counts, the results were made public immediately.

Although totals for the recount are not yet available, information from witnesses indicates that PAN candidate Felipe Calderon lost thousands of votes but Andrés Manuel López Obrador lost almost none.

CEPR’s analysis also confirmed that 61,192 of 126,139 ballot boxes contained “adding up” errors. Election workers received a fixed and recorded number of blank ballots for each ballot box, and were instructed to keep track of them. Yet for nearly half of all ballot boxes, the total votes plus leftover blank ballots did not add up to the number of ballots received.

“Without a full recount, it’s hard to have confidence in the result of a close election like this, especially with such a huge level of errors and the authorities withholding important information,”